3. Linear Fit â Find the RelationshipOK, at some point I will ask you to find the relationship between two variables. What Iâm asking is if X doubles how much does Y change? The more astute will realize this sounds like Iâm asking for an equation. Your calculator can find the equation implicit in a set of data by doing something called Regression. You may have learned how to do linear or quadratic regressions in math class. Your calculator can do all the work for you. a) Enter your data into your list b) Hit (stat) and select the âcalcâ menu c) Select the regression you want. You may have to think about what your graph looks like and decide which type of function makes that type of graph. d) By default the calculator looks for your data in L1 and L2. e) Hit enter and your equation will be displayed. f) Enter your data into (Y=) and see if it matches your data.